From 35c01159c24b5b1f9f0ac5de0fa37f206aa8a1ed Mon Sep 17 00:00:00 2001
From: Brandon Dyck <brandon@dyck.us>
Date: Sun, 12 Dec 2021 16:04:35 -0700
Subject: [PATCH] Support Wayland in build.zig

---
 build.zig | 74 ++++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 59 insertions(+), 15 deletions(-)

diff --git a/build.zig b/build.zig
index 19910d7..2e65f5c 100644
--- a/build.zig
+++ b/build.zig
@@ -9,6 +9,32 @@ const base_cflags: []const []const u8 = &.{
     "-Wno-implicit-fallthrough",
 };
 
+const Backend = enum {
+    default,
+    x11,
+    wayland,
+    opengl,
+    gdi,
+};
+
+const ConfigError = error {
+    PlatformNotSupported,
+    BackendNotSupported,
+};
+
+/// Returns a comma-separated list of the names of an enum's values
+/// in declaration order.
+fn enumNames(comptime E: type) []const u8 {
+    var s: []const u8 = &[_]u8{};
+    for (std.enums.values(E)) |value| {
+        if (s.len > 0) {
+            s = s ++ ", ";
+        }
+        s = s ++ @tagName(value);
+    }
+    return s;
+}
+
 pub fn build(b: *std.build.Builder) !void {
     const mode = b.standardReleaseOptions();
     const target = b.standardTargetOptions(.{});
@@ -25,7 +51,7 @@ pub fn build(b: *std.build.Builder) !void {
         "src/MiniFB_timer.c",
     });
 
-    const use_opengl = b.option(bool, "opengl", "Use OpenGL") orelse false;
+    const use_backend = b.option(Backend, "backend", "Which rendering back-end to use (" ++ enumNames(Backend) ++ ")") orelse .default;
 
     const lib = b.addStaticLibrary("minifb-zig-port", null);
     lib.addIncludeDir("src");
@@ -37,29 +63,47 @@ pub fn build(b: *std.build.Builder) !void {
     switch (target.getOsTag()) {
         std.Target.Os.Tag.windows => {
             try c_sources.append("src/windows/WinMiniFB.c");
-            lib.linkSystemLibraryName("gdi32");
-            if (use_opengl) {
-                try c_flags.append("-DUSE_OPENGL_API");
-                try c_sources.append("src/gl/MiniFB_GL.c");
-                lib.linkSystemLibraryName("opengl32");
+            lib.linkSystemLibrary("gdi32");
+            switch (use_backend) {
+                .gdi, .default => {},
+                .opengl => {
+                    try c_flags.append("-DUSE_OPENGL_API");
+                    try c_sources.append("src/gl/MiniFB_GL.c");
+                    lib.linkSystemLibraryName("opengl32");
+                },
+                else => {
+                    return ConfigError.BackendNotSupported;
+                }
             }
         },
         std.Target.Os.Tag.linux => {
             try c_sources.append("src/MiniFB_linux.c");
-            try c_sources.append("src/x11/X11MiniFB.c");
             lib.linkSystemLibrary("rt");
-            lib.linkSystemLibrary("X11");
+            switch (use_backend) {
+                .x11, .default => {
+                    try c_sources.append("src/x11/X11MiniFB.c");
+                    lib.linkSystemLibrary("X11");
+                },
+                .opengl => {
+                    try c_sources.append("src/x11/X11MiniFB.c");
+                    lib.linkSystemLibrary("X11");
 
-            if (use_opengl) {
-                try c_flags.append("-DUSE_OPENGL_API");
-                try c_sources.append("src/gl/MiniFB_GL.c");
-                lib.linkSystemLibrary("GL");
+                    try c_flags.append("-DUSE_OPENGL_API");
+                    try c_sources.append("src/gl/MiniFB_GL.c");
+                    lib.linkSystemLibrary("GL");
+                },
+                .wayland => {
+                    try c_sources.append("src/wayland/WaylandMiniFB.c");
+                    lib.linkSystemLibrary("wayland-client");
+                    lib.linkSystemLibrary("wayland-cursor");
+                },
+                else => {
+                    return ConfigError.BackendNotSupported;
+                }
             }
-            
-            // TODO wayland
         },
         else => {
-            return error.PlatformNotSupported;
+            return ConfigError.PlatformNotSupported;
         },
     }